CN105743257B - A kind of individual layer lap winding magnetic flux switches brushless electric machine - Google Patents

Abstract

The invention discloses a single-layer stacked winding magnetic flux switching brushless motor. The design method of the single-layer stacked winding is different from the fixed structure of the traditional double-layer concentrated winding "one coil corresponds to one stator core unit". The minimum is the principle of choosing the stator slots to place the two conductor sides of the coils to obtain the maximum pitch factor. In addition, only wires belonging to the same phase winding are placed in each stator slot, which improves the insulation capacity between different phase windings. The winding design method of the present invention makes the coil pitch factor of the magnetic flux switching brushless motor reach 1, which not only improves the fundamental wave amplitude and power (torque) density of the no-load induced potential of each phase, but also reduces the embedded wire and insulation of the winding The difficulty of the process reflects the superiority of the single-layer stacked winding flux switching brushless motor.

Description

A Flux Switching Brushless Motor with Single Laminated Winding

technical field

The invention belongs to the field of motor winding structure design, and relates to a single-layer stacked winding design method based on a flux-switching brushless motor. performance, suitable for high power applications.

Background technique

Flux switching permanent magnet motor is a new type of stator permanent magnet motor. Its stator core is assembled from a "U" shaped magnetic core and tangentially alternately magnetized permanent magnets, which is easy to form a magnetic concentration effect. The armature coil It straddles the stator slots on both sides of the stator core unit composed of two "U"-shaped permeable cores and a permanent magnet embedded in the middle, so that the armature reaction magnetic field and the permanent magnetic field are connected in parallel on the magnetic circuit, which has a strong Anti-demagnetization ability, compared with doubly salient motors and flux reversal motors, has higher torque (power) density and reliability, especially suitable for high-performance drives and high-power applications. The armature winding adopts fractional slot concentrated winding coils, each coil straddles the slots on both sides of a stator core unit, the ends are short, the amount of copper used is small, and the copper consumption is small, which effectively improves the efficiency of the motor. In addition, the inherent winding complementarity of the flux switching motor can effectively reduce or cancel the even harmonic components in the permanent magnet flux linkage and no-load induced potential waveform, so that the motor adopts fractional slot concentrated armature winding and rotor straight slot Higher sine degree can be obtained under certain conditions, especially suitable for AC speed regulation applications.

Based on the above advantages, the existing flux-switching brushless motor and the new topology based on the principle of flux switching all adopt fractional slot centralized armature windings. However, the fractional-slot concentrated winding structure has its own inherent drawbacks, including:

1) Additional harmonic components and the parasitic effects they cause, such as noise, vibration, torque fluctuation, unbalanced magnetic pull, etc.;

2) Each armature coil straddles the stator slots on both sides of a stator core unit, the coil span is fixed as the stator slot pitch, and the coil pitch angle is never equal to the rotor pole pitch, resulting in no-load induction potential of the coil The distance factor is always less than 1, which limits the amplitude of the no-load induced potential fundamental component of each phase of the flux switching motor;

3) The salient pole effect is weakened, so that the reluctance torque is almost 0;

4) For the double-layer concentrated winding, wires of different phase windings are placed in each stator slot, which increases the difficulty of phase-to-phase insulation.

These problems are especially prominent in flux-switching motors with low pitch factor and poor winding complementarity, which greatly limit the output and overall performance of the motor.

Contents of the invention

Technical problem: The technical problem to be solved by the present invention is to provide a single-layer stacked winding flux-switching brushless motor and its winding design method, changing the formation method of the armature coil, so that the no-load induced potential pitch factor of each phase winding reaches 1. Effectively increase the amplitude of the fundamental wave component of the no-load induced potential of each phase, thereby increasing the torque (power) density.

Technical solution: The present invention is a single-layer stacked winding magnetic flux switching brushless motor. The armature winding of the brushless motor adopts a single-layer stacked winding connection method with a coil span greater than the stator slot pitch. Each armature coil spans multiple In the stator slots on both sides of a stator core unit, only coil conductors belonging to the same phase winding are placed in each stator slot; the number of armature winding coils 2 is equal to half of the number of stator slots, and there is overlap between the coils of different phase windings ; Its innovation is that the single-layer stacked winding connection method is no longer limited to the fixed structure of one stator core unit corresponding to one armature coil in the traditional centralized winding connection method, but the coil is placed in the stator slot according to the principle of minimum short-distance angle Its two conductor sides make the coil pitch angle equal to the rotor pole pitch, so that the short pitch angle of the coil is 0, so as to obtain the maximum pitch factor, so that the pitch factor of the no-load induced potential of each phase winding reaches 1, effectively improving each The magnitude of the fundamental component of the phase no-load induced potential, thereby increasing the torque power density; the m-phase single-layer winding design method specifically includes the following steps:

1) First, the phase difference α (electrical angle) between the no-load induced potentials of conductors in two adjacent stator slots is determined according to the number of stator slots N _s of the motor and the number of rotor poles N _r , the formula is as follows:

Draw the star phasor diagram corresponding to the no-load induced potential of N _s slot conductors in turn;

2) Based on the star-shaped phasor diagram of the no-load induced potential of the slot conductor, two slot conductors whose no-load induced potential phase difference is 180° electrical angle are connected to form two conductor sides of a coil, and a total of N _s /2 independent coils can be formed. the coil;

3) Based on the no-load induced potential star diagram of N _s /2 coils obtained in 2), two coils with complementary windings are connected in series to form a coil group, thus forming a total of N _s /4 coil groups, each The phase difference of the no-load induced potential of two coils in a coil group is 0° or 180° electrical angle, so the distribution factor of the fundamental wave component of the no-load induced potential of the coil group is 1, and the even in the no-load induced potential of a single coil The sub-harmonic components cancel each other out, so that the harmonic content of the no-load induction potential of the coil group is reduced; based on the principle of maximizing the no-load induction potential of each phase winding, the phase difference of the no-load induction potential in the N _s /4 coil groups is the smallest N _s /(4m) coil groups are connected into a phase winding, so as to obtain the coil composition of the first phase winding; if there is no coil with winding complementarity, the phase difference of the no-load induced potential among the N _s /2 coils is the smallest The N _s /(2m) coils are connected to form a phase winding, so as to obtain the coil composition of the first phase winding; where m is the number of phases;

4) According to the phase relationship between the phase windings in the m-phase symmetrical winding, that is, the phase difference between the no-load induced potentials of adjacent two-phase windings is 2π/m (m≥3) or π/m (m=2) , determine the coil composition of the other m-1 phase windings in turn, so as to obtain the composition mode of the m-phase symmetrical armature winding.

in,

The number of stator slots N _s and the number of rotor poles N _r of the motor satisfy one of the following equations:

Among them, N _s , N _r , and k are all positive integers, and the number of stator slots N _s is an even multiple of the number of phases m.

The two conductor sides of each armature coil of the motor occupy an entire stator slot, and are not shared with other phase coil conductors.

The number of armature winding coils of this motor is half of the number N _s of stator slots.

In the step 2), for the mutually independent coils formed, the pitch of any coil is equal to the pole pitch, that is, full-pitch coils.

According to step 2), the two conductor no-load induced potentials of any coil formed have a phase difference of 180° electrical angle, which can ensure that the no-load induced potential of each coil obtains the maximum value, that is, the scalar sum of the no-load induced potentials of the two conductors of the coil, The coil pitch factor is 1.

In said step 3), the two coils with winding complementarity, if the no-load induced potential phase difference of the two complementary coils is 180° electrical angle, then reversely connected in series; if the no-load induced potential phase difference of the two complementary coils If the difference is 0 degrees, they are connected in forward direction.

The excitation source of the brushless motor is a permanent magnet, an electric excitation coil, or a hybrid excitation combining a permanent magnet and an electric excitation coil, or a memory permanent magnet method.

The method of the present invention is used to guide the formation of the armature winding coil of the magnetic flux switching brushless motor with specific cogging and the composition form of each phase winding. The pitch factor of the fundamental wave of the electric potential increases the amplitude of the fundamental wave of the no-load induced electric potential and the power density of the flux switching motor. The invention aims at improving the pitch factor of the motor and the amplitude of the fundamental wave of the no-load induced potential, while reducing the difficulty of the winding embedding and insulation process. It is suitable for pure electric excitation motors and hybrid excitation motors.

Beneficial effects: Compared with the prior art, the armature coil of the present invention is no longer limited to a fixed structure in which one stator core unit corresponds to one armature coil, but the coil is placed in two stator slots according to the principle of minimum short-distance angle. conductor side to obtain the maximum pitch factor, enabling the motor to achieve the following advantages:

1) The overlapping winding connection method is used to increase the pitch factor of the no-load induced potential of each coil, thereby increasing the amplitude of the fundamental component of the no-load induced potential of the coil;

2) Each phase winding is connected by the coil with the smallest phase difference of the induced potential, so that the fundamental winding factor of the no-load induced potential of each phase winding is high, thereby increasing the amplitude of the fundamental component of the no-load induced potential of each phase;

3) Further, the motor torque (power) is effectively improved, which greatly increases the torque (power) density of the motor;

4) The single-layer stacked winding connection method is adopted, and only the wires belonging to the same phase winding are placed in each stator slot, which improves the insulation capacity between different phase windings, reduces insulation difficulty and insulation cost, and improves slot utilization.

Description of drawings

Figure 1 is a schematic cross-sectional structure diagram of a three-phase stator, 24-slot rotor, and 16-pole single-layer stacked winding flux-switching permanent magnet brushless motor.

Fig. 2 is a star diagram of the slot conductor potential of a permanent magnet brushless motor with 24 slots in the stator and a 16-pole magnetic flux switching permanent magnet motor, and a star diagram of the no-load induced potential of the coil with a three-phase single-layer stacked winding structure. Among them, the no-load induction potential polarity of the slot conductor n' is opposite to that of n, that is, in A1 (201, 204'), A2 (207, 210'), A3 (213, 216'), and A4 (219, 222') , 201, 204' are opposite in polarity, 207, 210' in opposite polarity, 213, 216' in opposite polarity, 219, 222' in opposite polarity; the same is true for the other two phases B1 and C1. The phase difference between the no-load induced potential n and (n+1)’ of the slot conductor is 120° (electrical angle), and the phase difference α between the no-load induced potential n and n+1 of the adjacent slot conductor is 60° (electrical angle).

Figure 3 shows the coil connection method of a three-phase double-layer fractional slot centralized armature winding structure for a permanent magnet brushless motor with 24 slots in the stator and a 16-pole magnetic flux switching permanent magnet motor.

Figure 4 shows the coil connection method of a three-phase single-layer stacked winding structure for a permanent magnet brushless motor with 24 slots in the stator and a 16-pole magnetic flux switching permanent magnet motor.

Fig. 5 shows the characteristics of the torque variation with the current density of a permanent magnet brushless motor with 24 slots in the stator and a 16-pole magnetic flux switching permanent magnet brushless motor respectively adopting the two armature winding structures in Fig. 2 .

Detailed ways

The present invention will be further described below in conjunction with the embodiments and the accompanying drawings.

A single-layer stacked winding magnetic flux switching brushless motor of the present invention includes a stator 1, a rotor 4 and a rotating shaft 5, the rotor 4 is opposite to the stator 1, and there is a gap between the rotor 4 and the stator 1, and the rotating shaft 5 is fixedly connected to the rotor 4 superior. Both the stator 1 and the rotor 4 are salient pole structures. The stator 1 includes a stator core unit and a single-layer laminated winding coil 2 . Each stator core unit includes two U-shaped stator cores 101 and a permanent magnet 3 embedded between the two U-shaped stator cores 101 . The permanent magnets 3 are magnetized tangentially, and the directions of magnetization of two adjacent permanent magnets 3 are opposite. A stator slot 201 is formed between two adjacent stator core units. The single-layer laminated winding coil 2 straddles the stator slots on both sides of multiple stator core units, and the winding coils of different phases overlap. Only coil conductors belonging to the same phase winding are placed in each stator slot, and the number of armature winding coils 2 is equal to half of the number of stator slots. The stator and rotor cores are made of magnetically permeable materials. The permanent magnet 3 is made of permanent magnet material, preferably NdFeB, ferrite, or samarium cobalt.

Further, the number of armature winding coils 2 is equal to half of the number N _s of the stator slots 201 , N _s is an even multiple of the phase number m, ie N _s =2jm, j is a positive integer.

Further, the rotor 4 can be located inside the stator 1 or outside the stator 1 .

Further, one of the following equations is satisfied between the number of poles N _r of the rotor 4 and the number of slots N _s of the stator:

Wherein, N _s , N _r , and k are all positive integers.

Further, the single-layer laminated winding flux-switching brushless motor can be a pure permanent magnet excitation motor, a pure electric excitation motor, or a hybrid excitation motor, including an online charging and demagnetization memory motor, and the motor can be used as a The power generation operation can also be used for electric operation.

Different from the traditional flux-switching brushless motor, the single-layer stacked winding flux-switching brushless motor proposed by the present invention adopts a single-layer stacked winding connection mode, and each armature coil spans multiple stator core units, and the winding coils of different phases There is an overlap between them, and the two conductor sides of each coil occupy an entire stator slot, and are not shared with other phase coil conductors. Concrete implementation scheme is as follows:

1) First, the phase difference α (electrical angle) between the no-load induced potentials of conductors in two adjacent stator slots is determined according to the number of stator slots N _s of the motor and the number of rotor poles N _r , the formula is as follows:

Draw the phasor star diagram corresponding to the no-load induced potential of N _s slot conductors in turn.

2) Based on the slot conductor potential star diagram, connect two slot conductors whose no-load induced potential phase difference is 180° electrical angle to form two conductor sides of a coil, and the current polarity in these two conductor sides is opposite, and The coil pitch is equal to the pole pitch, that is, the full-pitch coil. Thus, a total of N _s /2 full-pitch coils can be formed, and the pitch factors of these N _s /2 full-pitch coils are all 1;

3) Based on the no-load induced potential star diagram of the N _s /2 coils, two coils with complementary windings are connected in series to form a coil group (if the no-load induced potential phase difference of the two complementary coils is 180° If the phase difference of the no-load induced potential of the two complementary coils is 0°, then they are connected in forward direction), thus forming a total of N _s /4 coil groups, and the two coils in each coil group The phase difference of the no-load induction potential is 0° or 180° electrical angle, so the distribution factor of the fundamental component of the no-load induction potential of the coil group is 1, and the even harmonic components in the no-load induction potential of a single coil cancel each other out, so that The harmonic content of the no-load induced potential of the coil group is reduced. Then, based on the principle of maximizing the no-load induction potential of each phase winding, the N _s /(4m) coil groups with the smallest no-load induction potential phase difference among the N _s /4 coil groups are connected into a phase winding, thus obtaining the first The coils of the phase windings form. It should be noted that if there is no coil with winding complementarity, the N _s /(2m) coils with the smallest no-load induced potential phase difference among the N _s /2 coils are connected to form a one-phase winding, thus obtaining the first The coils of the phase windings form.

4) According to the phase relationship between the phase windings in the m-phase symmetrical winding, that is, the phase difference between the no-load induced potentials of adjacent two-phase windings is 2π/m (m≥3) or π/m (m=2) , determine the coil composition of the other m-1 phase windings in turn, so as to obtain the composition mode of the m-phase symmetrical armature winding.

Designing single-layer stacked windings according to the above process can not only ensure the complementarity of the windings of the flux switching motor, but also improve the coil no-load induced potential pitch factor, increase the average value of the electromagnetic torque, and reduce the process difficulty of phase-to-phase insulation and cost.

Taking a three-phase stator, 24-slot rotor, 16-pole single-layer stacked winding flux-switching permanent magnet brushless motor as an example, its motor topology is shown in Figure 1. There are 24 stator core units and 24 stator slots on the stator, respectively. It is the first stator slot 201, the second stator slot 202, the third stator slot 203, ..., the twenty-fourth stator slot 224, and there are 12 armature winding coils 2, respectively the first coil A1, ..., the fourth Coil A4, fifth coil B1, ..., eighth coil B4, ninth coil C1, ..., twelfth coil C4, and each armature coil straddles the stator slots on both sides of the three stator core units, each The stator slots are only occupied by one-phase armature winding coils. There are a total of 16 rotor poles on the rotor, satisfying formula 3 in (1). The specific design process of its three-phase single-layer stacked winding structure is as follows:

1) According to the number of motor stator slots N _s =24 and the number of rotor poles N _r =16, determine the phase difference α=60° (electrical angle) between the no-load induced potentials of two adjacent stator slot conductors, thus obtaining 24 The no-load induced potential phasor star diagram of the stator slot conductor is shown in Fig. 2.

2) Based on the potential star diagram of the slot conductor, first judge and obtain the combination of slot conductors with a phase difference of no-load induced potential of 180 degrees in electrical angle, which are:

The first stator slot 201, the seventh stator slot 207, the thirteenth stator slot 213, the nineteenth stator slot 219 and the fourth stator slot 204, the tenth stator slot 210, the sixteenth stator slot 216, the twenty-second stator slot 222,

The second stator slot 202, the eighth stator slot 208, the fourteenth stator slot 214, the twentieth stator slot 220 and the twenty-third slot conductor 223, the fifth stator slot 205, the eleventh stator slot 211, the tenth stator slot seven stator slots 217,

The third stator slot 203, the ninth stator slot 209, the fifteenth stator slot 215, the twenty-first stator slot 221 and the sixth stator slot 206, the twelfth stator slot 212, the eighteenth stator slot 218, the second fourteen stator slots 224,

Connect the two slot conductors in the slot conductor combination of each stator slot above in series to form a coil, and each slot conductor cannot be combined repeatedly, so a total of 12 mutually independent coils are formed, namely the first coil A1 and the second coil A2 , third coil A3, fourth coil A4, fifth coil B1, sixth coil B2, seventh coil B3, eighth coil B4, ninth coil C1, tenth coil C2, eleventh coil C3, twelfth coil Coil C4, the no-load induced potential phases of the two conductor sides of each coil are opposite. Since the no-load induced potential of the coil is equal to the phasor difference of the induced potential of its two conductor sides, in the above connection mode, it can be guaranteed that the no-load induced potential of each coil reaches the maximum value, that is, the no-load induced potential of the two conductor sides of the coil The scalar sum of , the pitch factor is 1, which is twice the pitch factor of the traditional fractional slot concentrated winding connection method (as shown in Figure 3).

3) Next, determine whether the motor has winding complementarity. According to the relationship between the number of stator slots and the number of rotor poles that the flux switching motor needs to satisfy the winding complementarity, the stator 24-slot rotor 16-pole flux switching motor does not have winding complementarity. Therefore, among the 12 coils, the 4 coils with the smallest no-load induced potential phase difference are directly connected into a phase winding, so as to obtain the coil composition of the first phase winding, that is, the first coil A1, the second coil A2, and the third coil The A-phase winding formed by A3 and the fourth coil A4. The no-load induced potentials of the four coils of this phase winding have the same phase, so their distribution factor is 1.

4) In the three-phase symmetrical winding, the B and C phase windings are respectively +120° and -120° electrical angle different from the A phase winding, so the coil composition of the B and C phase windings can be easily obtained, as shown in Figure 4.

In order to reflect the advantages of the winding design method of the present invention, the three-phase winding structure according to the traditional fractional slot centralized winding connection method and the single-layer stacked winding connection method proposed by this patent is listed here, as shown in Fig. 3 and Fig. 4 . According to the double-layer fractional slot centralized winding connection method, each coil spans two adjacent stator slots, and the no-load induced potential phase difference between the two conductor sides of the coil is the no-load induced potential of the two adjacent stator slot conductors. The phase difference between the potentials is 120 degrees of electrical angle, so the pitch factor of the no-load induced potential of each coil is 0.5; and each armature coil of the three-phase single-layer stacked winding of the present invention spans three stator teeth In the stator slots on both sides of the unit, the phase difference of the no-load induced potentials on the two conductor sides of the coil is three times the phase difference between the no-load induced potentials of the two adjacent stator slot conductors, which is 360 degrees electrical angle, that is, the node The distance is equal to the pole distance, so the pitch factor of the no-load induced potential of each coil is 1, which is twice the pitch factor of the traditional fractional slot centralized armature coil.

Fig. 5 is the torque-current density curve of the 16-pole magnetic flux switching permanent magnet brushless motor with 24 slots in the stator and the two armature winding structures in Fig. 3 and Fig. 4 . Through comparison, it can be seen that under the single-layer stacked winding connection method, the electromagnetic torque of the motor is larger than that under the traditional connection method under different slot current densities, and the difference is even greater when the current density is relatively small. When the current density is 5A/mm ² , the output of the single-layer stacked winding flux-switching permanent magnet brushless motor is 1.75 times that of the traditional centralized winding flux-switching permanent magnet motor. The comparison results fully demonstrate that the design method of the single-layer stacked winding magnetic flux switching brushless motor winding of the present invention has innovation and superiority.

The above are only preferred embodiments of the present invention, and it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some conceivable improvements and equivalent replacements can also be made, which are essential to the present invention. The technical solutions after the claims are improved and replaced by equivalents all fall into the protection scope of the present invention.

Claims (8)

1. A single-layer lap winding magnetic flux switching brushless motor is characterized in that an armature winding (2) of the brushless motor adopts a single-layer lap winding connection mode, each armature winding coil crosses stator slots at two sides of a plurality of stator core units, and only coil conductors belonging to the same-phase armature winding are placed in each stator slot; the number of armature winding coils of the armature winding (2) is equal to half of the number of stator slots, and the armature winding coils of different phases are overlapped; the single-layer lap winding connection mode is not limited to a fixed structure that one stator core unit corresponds to one armature winding coil in a traditional centralized winding connection mode, but the armature winding coil is placed on two conductor sides according to the principle of minimum short-distance angle to obtain the maximum pitch factor, so that the pitch factor of each phase of winding reaches 1, the amplitude of each phase of no-load induced potential fundamental wave component is effectively improved, and the torque power density is improved; the design method of the m-phase single-layer lap winding specifically comprises the following steps:

1) firstly, according to the number N of stator slots of the motor_sAnd number of rotor poles N_rDetermining α an electrical angle phase difference between no-load induced potentials of two adjacent stator slot conductors, the equation being as follows:

draw N in turn_sA star-shaped phasor diagram corresponding to the no-load induced potential of each slot conductor;

2) based on the slot conductor no-load induced potential star-shaped phasor diagram, two slot conductors with no-load induced potential phase difference of 180 electrical degrees are connected into two conductor edges of an armature winding coil, so that N can be formed_s2 independent armature winding coils;

3) based on N obtained in 2)_sA no-load induced potential star diagram of 2 armature winding coils, wherein two armature winding coils with winding complementarity are connected in series to form a coil group, thereby forming N_sThe phase difference of the no-load induction potentials of the two armature winding coils in each coil group is 0 DEG or 180 DEG, so that the distribution factor of the no-load induction potential fundamental wave component of the coil group is 1, and even harmonic components in the no-load induction potentials of the single armature winding coils are mutually offset, so that the harmonic content of the no-load induction potentials of the coil groups is reduced; based on the principle of maximizing the no-load induced potential of each phase winding, N is calculated_sN with minimum airborne induced potential phase difference in 4 coil groups_s(4m) connecting the coil groups into a phase winding, thereby obtaining a first-phase armature winding coil structure; if no coil with winding complementarity exists, N is_sN with minimum phase difference of air-load induced potentials in 2 coils_s/(2m) coils connected to form one phaseWinding to obtain a first phase armature winding coil configuration; wherein m is the number of phases;

4) according to the phase relation among the windings of each phase in the m symmetrical windings, namely the phase difference between the no-load induced potentials of the adjacent two-phase windings is 2 pi/m, m is larger than or equal to 3 or pi/m, and m is 2, the structure of the coils of other m-1-phase armature windings is sequentially determined, so that the structure mode of the m symmetrical armature windings is obtained.

2. The single layer stacked winding flux switching brushless motor of claim 1, wherein the motor has a number N of stator slots_sAnd number of rotor poles N_rOne of the following equations is satisfied:

<mrow> <mn>1.</mn> <msub> <mi>N</mi> <mi>r</mi> </msub> <mo>=</mo> <msub> <mi>N</mi> <mi>s</mi> </msub> <mo>&amp;PlusMinus;</mo> <mfrac> <msub> <mi>N</mi> <mi>s</mi> </msub> <mrow> <mn>4</mn> <mi>k</mi> </mrow> </mfrac> <mo>,</mo> <mi>k</mi> <mo>&amp;GreaterEqual;</mo> <mn>1</mn> </mrow>

<mrow> <mn>2.</mn> <msub> <mi>N</mi> <mi>r</mi> </msub> <mo>=</mo> <mfrac> <msub> <mi>N</mi> <mi>s</mi> </msub> <mn>2</mn> </mfrac> <mo>&amp;PlusMinus;</mo> <mfrac> <msub> <mi>N</mi> <mi>s</mi> </msub> <mrow> <mn>4</mn> <mi>k</mi> </mrow> </mfrac> <mo>,</mo> <mi>k</mi> <mo>&amp;GreaterEqual;</mo> <mn>1</mn> </mrow>

<mrow> <mn>3.</mn> <msub> <mi>N</mi> <mi>r</mi> </msub> <mo>=</mo> <msub> <mi>N</mi> <mi>s</mi> </msub> <mo>&amp;PlusMinus;</mo> <mfrac> <msub> <mi>N</mi> <mi>s</mi> </msub> <mrow> <mn>2</mn> <mi>k</mi> <mo>+</mo> <mn>1</mn> </mrow> </mfrac> <mo>,</mo> <mi>k</mi> <mo>&amp;GreaterEqual;</mo> <mn>1</mn> </mrow>

wherein N is_s、N_rK is a positive integer, and the number of stator slots is N_sAn even multiple of the number m of phases.

3. A single layer stacked winding flux switching brushless electric machine according to claim 1, wherein both conductor sides of each armature winding coil of the machine are exclusive of an entire stator slot, respectively, and are not shared with other phase armature winding coil conductors.

4. A single layer stacked winding flux switching brushless motor according to claim 3, wherein the number of armature winding coils of the motor is the number of stator slots N_sHalf of that.

5. The single-layer stacked winding flux switching brushless motor according to claim 1, wherein in the step 2), the independent armature winding coils are formed, and the pitch of any armature winding coil is equal to the pole pitch, that is, a full pitch coil.

6. The single-layer stacked winding flux-switching brushless motor according to claim 5, wherein the two conductor no-load induction potentials of any armature winding coil formed according to step 2) are 180 ° out of phase, so that each coil no-load induction potential can be guaranteed to have a maximum value equal to the scalar sum of the two conductor no-load induction potentials of the coil, and the coil pitch factor is 1.

7. The single-layer stacked winding flux-switching brushless motor according to claim 1, wherein in the step 3), the two armature winding coils having winding complementarity are connected in series in an opposite direction if no-load induced potentials of the two complementary armature winding coils are 180 ° in electrical angle phase difference; if the no-load induced potential phase difference of the two complementary armature winding coils is 0 degrees, the two complementary armature winding coils are connected in series in the positive direction.

8. The single-layer lap winding flux-switching brushless motor according to claim 1, wherein the excitation source of the brushless motor is a permanent magnet, an electric field coil, or a hybrid excitation combining a permanent magnet and an electric field coil, or a memory permanent magnet system.